1. Field of the Invention
This invention relates to a noise reduction apparatus and method and to a noise reduction program.
2. Description of the Related Art
CCDs used in digital still cameras are continuing to be improved in terms of number of pixels and sensitivity. The influence of noise, therefore, has become a problem.
Use of a low-pass filter or median filter, etc., to remove noise from a video signal obtained by sensing an image has been considered (see the specification of Japanese Patent Application Laid-Open No. 4-235472). Further, the removal of noise from an image without detracting from image sharpness also has been considered (see the specification of Japanese Patent Application Laid-Open No. 2002-222416).
It is still difficult, however, to remove noise completely.